1. Field of the Invention
The invention relates to operating a steam generator in a fabric treatment appliance.
2. Description of the Related Art
Some fabric treatment appliances, such as a washing machine, a clothes dryer, and a fabric refreshing or revitalizing machine, use steam generators for various reasons. The steam from the steam generator can be used to, for example, heat water, heat a load of fabric items and any water absorbed by the fabric items, dewrinkle fabric items, remove odors from fabric items, sanitize the fabric items, and sanitize components of the fabric treatment appliance.
A common problem associated with steam generators involves the formation of deposits, such as scale and sludge, within the steam generation chamber. Water supplies for many households may contain dissolved substances, such as calcium and magnesium, which can lead to the formation of deposits in the steam generation chamber when the water is heated. Scale and sludge are, respectively, hard and soft deposits; in some conditions, the hard scale tends to deposit on the inner walls of the structure forming the steam generation chamber, and the soft sludge can settle to the bottom of the steam generator. Formation of scale and sludge can detrimentally affect heat transfer and thereby decrease the steam generating efficiency of the steam generator (i.e., energy or heat input compared to resulting steam output). Further, scale and sludge can hinder fluid and steam flow through and out of the steam generator and can lead to a reduced operational life of the heater or steam generator.